The National Fire Protection Association (NFPA) promulgates standards relating to fire protection such as, for example, NFPA Standard 13 (2007) (hereinafter “NFPA-13 (2007)”), portions of which are incorporated in their entirety herein by reference. For example Chapter 8, Section 8.8 of NFPA-13 (2007), which is incorporated herein in its entirety is applicable to extended coverage upright and pendent spray sprinklers. This section provides that for extended coverage sprinklers the maximum allowable coverage for extra hazard is 196 square feet, which is applicable to densities of 0.25 gpm/sq. ft. and higher. To address this requirement, Tyco Fire & Building Products introduced an upright extended coverage sprinkler having a nominal K-factor of 25 (EC K-25). At its minimum operating pressure of 7 psi., and the maximum spacing of 196 sq. ft., the existing EC K-25 is applicable to densities of 0.36 gpm/sq. ft. and higher. While effectively addressing the needs for extended coverage, the average density of the sprinkler presents an overdischarge of fluid for areas requiring a design density less than 0.36 gpm/sq. ft.
NFPA provides other provisions which are applicable to extended coverage and/or control mode sprinklers and systems. Chapter 11 of NFPA-13 (2007), which is incorporated herein by reference is applicable to the design approaches in configuring a preferred sprinkler system. Chapter 12 of NFPA-13 (2007), which is incorporated herein by reference in its entirety is directed to the general requirements for storage. Section 14.2 of NFPA-13 (2007), which is incorporated herein by reference in its entirety is directed to control mode density-area sprinkler protection criteria for palletized, solid piled, bin box or shelf storage of Class I through Class IV Commodities. Section 15.2 of NFPA-13 (2007), which is incorporated herein by reference in its entirety is directed to control mode density-area sprinkler protection criteria for palletized, solid piled, bin box or shelf storage of Plastic and Rubber Commodities.
Other applicable standards include: Underwriter Laboratories, Inc. Specification UL 199, and Factory Mutual Approval Standard entitled, “Class Number 2000: Automatic Control Mode Sprinklers For Fire Protection” (March 2006).